Thee "receipt" might actually contribute in developing countries to voter pressure. Imagine a wife in Pakistan voting for a party which her husband does not approve off, and then the husband tells his wife to check with the receipt for whom she has voted. Family-based voting might become a lot more prevalent.
Or she can destroy it, and tell her husband no, fuck off.
While this sounds simple. What do you think would the abusive husband do?
This is a common issue in the developing world. Just destroying the paper is not a solution as the husband will want to know for whom she voted.